WISE 1639−6847

WISE J163940.83−684738.6

WISE 1639-6847 in near-infrared with Hubble. It shows the brown dwarf moving within 1 ½ years
Credit: Hubble Space Telescope; Fontanive et al.
Observation data
Epoch J2000      Equinox J2000
Constellation Triangulum Australe
Right ascension 16h 39m 39.730s[1]
Declination −68° 47′ 06.693″[1]
Characteristics
Spectral type Y0 pec[2]
Astrometry
Proper motion (μ) RA: 576.94±0.22 mas/yr[1]
Dec.: −3108.48±0.21 mas/yr[1]
Parallax (π)211.11 ± 0.56 mas[1]
Distance15.45 ± 0.04 ly
(4.74 ± 0.01 pc)
Other designations
GJ 12393[3],WISEPC J163940.83-684738.6[4]
WISE 1639-6847[5]
W1639[4]
Database references
SIMBADdata
WISE 1639−6847 is located in the constellation Triangulum Australe.
WISE 1639−6847 is located in the constellation Triangulum Australe.
            WISE 1639−6847
Location of WISE 1639−6847 in the constellation Triangulum Australe

WISE J163940.83−684738.6 (designation is abbreviated to WISE 1639−6847[5], or W1639[4]) is a brown dwarf of spectral class Y0 pec,[2] located in constellation Triangulum Australe (it's the nearest star / brown dwarf in this constellation) at 15.5 light-years from Earth.[1] It is the second closest Y-dwarf as of February 2024.

Discovery

WISE 1639−6847 was discovered in 2012 by C. G. Tinney et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite — NASA infrared-wavelength 40 cm (16 in) space telescope, which mission lasted from December 2009 to February 2011.

In 2012 Tinney et al. carried out follow-up observations of WISE 1639−6847 using the FourStar infrared mosaic camera mounted on the 6.5 m Magellan Baade telescope at Las Campanas Observatory, Chile (on 2012 May 10–11 (UT)); and spectroscopy using the Folded-port Infrared Echellette (FIRE) also mounted on the 6.5 m Magellan Baade telescope (on 2012 July 10 (UT)).

In 2012 Tinney et al. published a paper in The Astrophysical Journal, where they presented discovery of a newfound by WISE Y-type brown dwarf WISE 1639−6847 (the only brown dwarf discovery, presented in the article): the paper was accepted for publication on 20 September 2012, submitted to arXiv on 27 September 2012, and published in November 2012.[4]

Physical properties

WISE 1639−6847 has absolute magnitude in J-band 22.14 ± 0.22.[4] WISE 1639−6847 was first classified to have a spectral type between Y0 and Y0.5. Observations with Hubble WFC3 near-infrared grism spectroscopy showed that the J-band peak matched with the Y0 standard. The Y-band peak and the Y-J color showed that it was unusual compared to other Y-dwarfs and therefore a spectral type of Y0 pec was applied. The pec stands for peculiar or unusual.[2] Modelling of this Y-dwarf struggles to reproduce the spectrum. Only with rather unrealistic high temperature and low gravity it was possible to reproduce the spectrum.[6]

See also

References

  1. ^ a b c d e Fontanive, C.; Bedin, L. R.; Bardalez Gagliuffi, D. C. (February 2021). "The Y dwarf population with HST: unlocking the secrets of our coolest neighbours – I. Overview and first astrometric results". Monthly Notices of the Royal Astronomical Society. 501 (1): 911–915. arXiv:2011.13873. Bibcode:2021MNRAS.501..911F. doi:10.1093/mnras/staa3732. S2CID 227208804.
  2. ^ a b c Schneider, Adam C.; Cushing, Michael C.; Kirkpatrick, J. Davy; Gelino, Christopher R.; Mace, Gregory N.; Wright, Edward L.; Eisenhardt, Peter R.; Skrutskie, M. F.; Griffith, Roger L.; Marsh, Kenneth A. (2015-05-01). "Hubble Space Telescope Spectroscopy of Brown Dwarfs Discovered with the Wide-field Infrared Survey Explorer". The Astrophysical Journal. 804 (2): 92. arXiv:1502.05365. Bibcode:2015ApJ...804...92S. doi:10.1088/0004-637X/804/2/92. ISSN 0004-637X.
  3. ^ Golovin, Alex; Reffert, Sabine; Just, Andreas; Jordan, Stefan; Vani, Akash; Jahreiß, Hartmut (November 2022). "The Fifth Catalogue of Nearby Stars (CNS5)". Astronomy & Astrophysics. 670: A19. arXiv:2211.01449. Bibcode:2023A&A...670A..19G. doi:10.1051/0004-6361/202244250. Catalogue can be accessed here.
  4. ^ a b c d e Tinney, Chris G.; Faherty, Jacqueline K.; Kirkpatrick, J. Davy; Wright, Edward L.; Gelino, Christopher R.; Cushing, Michael C.; Griffith, Roger L.; Salter, Graeme (2012). "WISE J163940.83–684738.6: A Y Dwarf Identified by Methane Imaging". The Astrophysical Journal. 759 (4): 60. arXiv:1209.6123. Bibcode:2012ApJ...759...60T. doi:10.1088/0004-637X/759/1/60. S2CID 119231938.
  5. ^ a b Dupuy, T. J.; Kraus, A. L. (2013). "Distances, Luminosities, and Temperatures of the Coldest Known Substellar Objects". Science. 341 (6153): 1492–5. arXiv:1309.1422. Bibcode:2013Sci...341.1492D. doi:10.1126/science.1241917. PMID 24009359. S2CID 30379513.
  6. ^ Zalesky, Joseph A.; Line, Michael R.; Schneider, Adam C.; Patience, Jennifer (2019-05-01). "A Uniform Retrieval Analysis of Ultra-cool Dwarfs. III. Properties of Y Dwarfs". The Astrophysical Journal. 877: 24. arXiv:1903.11658. Bibcode:2019ApJ...877...24Z. doi:10.3847/1538-4357/ab16db. ISSN 0004-637X.